| 摘要 |
When a casing (1) and a retainer (4) are rotated around their axis, torque is transmitted to the groove (3b) of each rotary member (3) via the rolling elements (5) and the pair of rotary members rotate together with the casing. When a revolution difference occurs between said pair of rotary members, rolling elements retained in the guide slots (4c) of said retainer rolls along the grooves of said pair of rotary members to make reciprocal movement within the range of said guide slots. At this time, when a force which causes revolution difference between said pair of rotary members is applied from the side of only one of said pair of rotary members, since the rolling elements which come to the following side when revolution difference is occurring work to let trail the groove which comes to the leading side when revolution difference is occurring to their own movements, the reaction force occurring here works as a resistance to restrict the revolution difference between said pair of rotary members. This invention can therefore provide reliable torque-sensitive revolution difference restricting effects without need for addition of a special mechanism to obtain the revolution difference restricting effect. <IMAGE> <IMAGE> |
